LeetCode 2000+

Array / String

• 1 Two Sum
• 49 Group Anagrams
• 58 Length of Last Word
• 217 Contains Duplicate
• 242. Valid Anagram
• 383 Ransom Note
• 929 Unique Email Addresses
• 1768 Merge Strings Alternately
• 1071 Greatest Common Divisor of Strings
• 1299 Replace Elements with Greatest Element on Right Side

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Two Pointers

• 88 Merge Sorted Array
• 125 Valid Palindrome
• 408 Valid Word Abbreviation

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Sliding Windows

• 3 Longest Substring Without Repeating Characters

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Binary Search

• 35 Search Insert Position
• 704 Binary Search

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Linked List

• 2 Add Two Numbers
• 19 Remove Nth Node From End of linked list
• 21 Merge Two Sorted Lists
• 86 Partition List
• 141 Linked List Cycle
• 203 Remove Linked List Elements
• 206 Reverse Linked List

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Stack

• 20 Valid Parentheses

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Tree

• 100 Same Tree

• 104 Maximum Depth of Binary Tree

• 110 Balanced Binary Tree

• 124 Binary Tree Maximum Path Sum

• 226 Invert Binary Tree

• 235 Lowest Common Ancestor of a Binary Search Tree

• 572 Subtree of Another Tree

• 617 Merge Two Binary Trees

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Heap

• 1046 Last Stone Weight

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Dynamic Programming

• 70 Climbing Stairs
• 198 House Robber
• 509 Fibonacci Number
• 746 Min Cost Climbing Stairs

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DFS (Island – Flood)

• 130 Surrounded Regions
• 200 Number of Islands
• 695 Max Area of Island
• 733 Flood Fill

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Two Pointers (Fast and Slow)

• 27 Remove Element
• 234 Palindrome Linked List

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Design

• 146 LRU Cache

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integer manipulation

• 7 Reverse Integer

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Math

• 263 Ugly Number

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Bit Manipulation

• 191 Number of 1 Bits

• 268 Missing Number

• 371 Sum of Two Integers

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Prefix and Suffix

• 238 Product of Array Except Self

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Buy and Sell Stock

• 121 Best Time to Buy and Sell Stock

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Contains Duplicate

• 217 Contains Duplicate

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Sum

• 15 3Sum
• 18 4Sum
• 454 4Sum II

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Single Number

• 136 Single Number

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Recommend Resources:

• The Difference between LeetCode 104 (Maximum Depth of Binary Tree) and LeetCode 124 (Binary Tree Maximum Path Sum)

• 20-Day-Challenge-List/Algorithm by uwspstar

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• How I would learn Leetcode if I could start over NeetCodeIO